(N/A) Given: Weight of adult $W = mg = 600 \, N$,height raised per step $h = 0.25 \, m$,step length $l = 1 \, m$,total distance $d = 6 \, km = 6000 \, m$.
Total number of steps $n = \frac{d}{l} = \frac{6000 \, m}{1 \, m} = 6000$.
Energy utilised per step $E_{step} = mgh = 600 \, N \times 0.25 \, m = 150 \, J$.
Total energy utilised in jogging $E_{total} = n \times E_{step} = 6000 \times 150 \, J = 9 \times 10^5 \, J$.
Given that the body converts $10 \, \%$ of food energy intake into work,let $E_{food}$ be the total energy intake.
$0.10 \times E_{food} = 9 \times 10^5 \, J$.
$E_{food} = \frac{9 \times 10^5}{0.10} = 9 \times 10^6 \, J$.